Django: the behavior of the underlying HTMLParser leading to DoS

An issue was discovered in Django 1.11.x before 1.11.23, 2.1.x before 2.1.11, and 2.2.x before 2.2.4. Due to the behaviour of the underlying HTMLParser, django.utils.html.striptags would be extremely slow to evaluate certain inputs containing large sequences of nested incomplete HTML entities...